Hydrolyzable silanes and polymerizable silanes with low viscosity and use thereof

ABSTRACT

The invention provides processes for making low viscosity condensates, condensates per se, and processes for making polymers from these condensates. The invention also encompasses the polymer products of these processes, especially articles for dental use. The condensates per se of the invention are of hydrolyzable silanes. The condensates can contain one or more elements selected from the group consisting of B, AI, P, Sn, Pb, the transition metals, the lanthanides and the actinides. Processes of the invention for making polymers from the condensates optionally include use of compounds that can be polymerized ionically or by radical reactions in addition to the hydrolyzable silanes. Curing of the polymers is optionally performed by photochemical, thermal or by redox-induction methods.

This application is the national phase under 35 U.S.C. § 371 of PCTInternational Application No. PCT/EP00/06639 which has an Internationalfiling date of Jul. 12, 2000, which designated the United States ofAmerica.

The invention relates to hydrolyzable and polymerizable silanes withlow-viscosity, processes for their preparation and their use, inparticular in dental compositions.

Hydrolyzable and polymerizable silanes are known from EP-A-0 682 033 andEP-A-0 450 624 which include hydroxyl or carbonyl groups or urethanegroups respectively. The molecules described there are relativelyinflexible and have a high condensate viscosity which makes it necessaryfor example when using composite materials to use diluting monomers.However, the addition of diluting monomers has the serious disadvantagethat there is the danger of an increased possibility of residual monomerrelease and thus of an increased toxicological unacceptability.

It is particularly necessary in the dental field to use low-viscosityand flexible molecules which do not however tend to evaporate out of theformulated compositions, as this leads to easy handling in terms of easeof removal from the storage containers and their acceptability in termsof health. Low-viscosity mixtures can also be mixed better and therebylead to improved, more homogeneous end-products.

The object of the present invention is to provide organically modifiedsilanes which can be hydrolyzed and polymerized and which are oflow-viscosity and flexible without evaporating out of the formulatedcompositions, and which can thus be processed alone for example toproduce dental compositions without requiring the addition of dilutingmonomers.

This object is achieved by hydrolyzable and polymerizable silanes of thegeneral formula I:B{(A)_(d)—R′—U—R′—SiX_(a)R_(b)}_(c)  (I)in which the radicals and indices have the following meaning:

B = a mono- to tetravalent, straight-chained or branched organic radicalwith at least one C═C double bond and 4 to 50 carbon atoms; X =hydrogen, halogen, hydroxy, alkoxy, acyloxy, alkylcarbonyl,alkoxycarbonyl or NR″₂; R = alkyl, alkenyl, aryl, alkylaryl orarylalkyl; R′ = alkylene, alkenylene, arylene, arylenealkylene oralkylenearylene each with 0 to 10 carbon atoms, these radicals beingable to be interrupted by oxygen and sulphur atoms or by amino groups;R″ = hydrogen, alkyl or aryl; A = C(O)O, OC(O)O, C(O), O, S, C(O)NR″,OC(O), NR″C(O); U = an inorganically modified organic radical whichcontains a siloxane, carbosilane or carbosiloxane framework with atleast two (siloxane, carbosiloxane) or one (carbosilane) silicon orgermanium atom and contains 1 to 15 C atoms as well as up to 5additional heteroatoms from the group O, S, N; a = 1, 2 or 3; b = 0, 1or 2; a + b = 3; c = 1, 2, 3 or 4; d = 0 or 1.

The silanes according to the invention are of low-viscosity and flexibleand do not evaporate out of the compositions formulated with them. Theycan be processed alone, in mixtures or together with other hydrolyzable,condensable or polymerizable components to produce scratch-resistantcoatings, filling, adhesion or sealing compounds, moulded bodies orembedding materials.

The silanes according to the invention can be universally used and canbe incorporated into an inorganic-organic composite system, i.e. into aninorganic-organic network.

The distance between silicon and reactive double bond can be set asdesired and the silane can also have several C═C double bonds at itsdisposal. Furthermore the chain between silicon and reactive double bondcontains no groups capable of developing hydrogen bridges.

The silanes of formula I can be polymerized via the radicals B andhydrolyzed via the radicals X. An inorganic network with Si—O—Si unitscan be constructed via the hydrolyzable groups, while the double bondscontained in radical B polymerize accompanied by the construction of anorganic network.

With regard to formula I and all subsequent formulae, the followingdefinitions of radicals apply quite generally.

The alkyl radicals are for example straight-chained, branched or cyclicradicals with 1 to 20, in particular with 1 to 10 carbon atoms andpreferably low alkyl radicals with 1 to 6, particularly preferably with1 to 4 carbon atoms. Special examples are methyl, ethyl, n-propyl,i-propyl, n-butyl, s-butyl, i-butyl, t-butyl, n-pentyl, n-hexyl,cyclohexyl, 2-ethylhexyl, dodecyl and octadecyl.

The alkenyl radicals are for example straight-chained, branched orcyclic radicals with 2 to 20, preferably with 2 to 10 carbon atoms andpreferably low alkenyl radicals with 2 to 6 carbon atoms, such as vinyl,allyl and 2-butenyl.

Preferred aryl radicals have 6-20, particularly preferably 6-15 carbonatoms. Preferred acyl radicals have 1-15 carbon atoms, preferably 1-10carbon atoms. Preferred arylalkyl and alkylaryl radicals contain 7-25,preferably 7-15 carbon atoms. Preferred alkylene radicals have 2-15,particularly preferably 2 to 10 C atoms. Preferred arylene radicals have6-25, particularly preferably 6-15 C atoms. Preferred alkylenearyleneradicals have 7-25, particularly preferably 7-15 C atoms. Preferredalkoxy, acyloxy, alkylcarbonyl or alkoxycarbonyl radicals have 1-15,particularly preferably 1-10 C atoms. Preferred alkylamino anddialkylamino radicals have 1-15, particularly preferably 1-10 C atoms.

Preferred aryl radicals are phenyl, biphenyl and naphthyl. The alkoxy,acyloxy, alkylamino, dialkylamino, alkylcarbonyl, alkoxycarbonyl,arylalkyl, alkylaryl, alkylene and alkylene and alkylenearylene radicalspreferably derive from the above-named alkyl and aryl radicals. Specialexamples are methoxy, ethoxy, n- and i-propoxy, n-, i-, s- and t-butoxy,monomethylamino, monoethylamino, dimethylamino, diethylamino,N-ethylanilino, acetyloxy, propionyloxy, methylcarbonyl, ethylcarbonyl,methoxycarbonyl, ethoxycarbonyl, benzyl, 2-phenylethyl and tolyl.

The named radicals can optionally carry one or more substituents, forexample halogen, alkyl, hydroxyalkyl, alkoxy, aryloxy, alkylcarbonyl,alkoxycarbonyl, furfuryl, tetrahydrofurfuryl, amino, monoalkylamino,dialkylamino, trialkylammonium, amido, hydroxy, formyl, carboxy,mercapto, cyano, isocyanato, nitro, epoxy, SO₃H or PO₄H₂.

Of the halogens, fluorine, chlorine and bromine and in particularchlorine are preferred.

For a=2 and b=2 respectively, the radicals X and R can each have thesame or a different meaning.

The radical B derives from a mono- to tetravalent, substituted orunsubstituted compound B((A)_(d)R′″)_(c). R′″ is here an unsaturatedorganic radical which is suitable for the addition of SiH groups in ahydrosilylation reaction and in the process converts into the radicalR′. R′″ is preferably a vinyl, allyl, butenyl or higher alkenyl radicalwhich preferably has no further substituents at the C═C double bond. Theradical B carries functional groups which are capable of polymerformation. These include in particular acrylate, methacrylate, (jointlycalled (meth)acrylate in the following), allyl, epoxy, oxetanyl,norbornenyl and vinylcyclopropyl groups.

Without limiting the general principle, specific representatives ofradical B (in the case of methacrylates the corresponding acrylates arealso always meant) are:

The radical B is in each case linked to a group —(A)_(n)—R′— via itsfree valencies.

The radical U derives from a substituted or unsubstituted compoundX_(a)R_(b)Si—R′—U—H. This compound is preferably prepared byhydrosilylation from a linear di- or oligo-hydrido silane H—U—H and anunsaturated silicon organic compound. Here, linear means the restrictionthat cyclosiloxanes hydridofunctionalized at the ring are not meant. α-and β-adducts can always occur during the hydrosilylation. According tothe invention the resulting mixture of the two is always meant for eachhydrosilylation.

Without limiting the general principle, specific representatives of theradical U are:

The silanes according to the invention can for example be prepared bysubjecting, in a manner known per se, a C═C unsaturated silane of thegeneral formula II:R′″—SiX_(a)R_(b)  (II)in which X,R,a,b and a+b are as defined in claim 1 and R′″, aspreviously mentioned, is an unsaturated organic radical which issuitable for the addition of Si—H groups in a hydrosilylation reactionand in the process changes into the radical R′ according to the abovedefinition, to an equimolar addition reaction with a compound of thegeneral formula H—U—H, the equimolar addition product being physicallyseparated if necessary. U has the above meaning. The equimolar additionproductH—U—R′—Si—X_(a)R_(b)  (III)is changed into a derivative according to the invention by subjecting itto a further addition reaction with a compound of the general formulaB((A)_(d)R′″)_(c). (IV) in which B,A,d,c and R′″ have the meaning givenabove.

In the following, the synthesis principles are explained in more detailusing specific reaction equations:

In all these reaction types, a repeated, up to quadruple, addition ofthe corresponding silanes to compounds B((A)_(d)R′″)_(c)(IV) with c=2, 3or 4 is possible.

Without limiting the general principle, specific examples of radicals—R′—SiX_(a)R_(b) (formula V) are:

-   —(CH₂)_(n)—Si(CH₃)₂(OC₂H₅), with n=0 to 10-   —(CH2)_(n)—Si(CH₃)(OC₂H₅)₂, with n=0 to 10-   —(CH₂)_(n)—Si(OC₂H₅)₃, with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)₂(OCH3), with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)(OCH₃)₂, with n=0 to 10-   —(CH₂)_(n)—Si(OC₂H₅)₃, with n=0 to 10-   —(CH₂)_(n)—Si(CH₃)₂(OCH₃), with n=0 to 10-   —(CH₂)_(n)—Si(CH₃)(OCH₃)₂, with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)₂(OC₂H₅), with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)(OC₂H₅)₂, with n=0 to 10-   —(CH₂)_(n)—Si(CH₃)(C₂H₅)(OCH₃), with n=0 to 10-   —(CH₂)_(n)—Si(CH₃)(C₂H₅)(OC₂H₅), with n=0 to 10-   —(CH₂)_(n)—Si(CH₃)(OC₂H₅)(OCH₃), with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)(OC₂H₅)(OCH₃), with n=0 to 10-   —(CH₂)_(n)—Si(OC₂H₅)₂(OCH₃), with n=0 to 10-   —(CH₂)_(n)—Si(OC₂H₅)(OCH₃)₂, with n=0 to 10-   —(CH₂)_(n)—Si(CH₃)(OC(CH₃)═CH₂)₂, with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)₂(C(CH₃)═CH₂)₂, with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)₂(OC(CH₃)═CH₂), with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)₂(OC(CH₃)═CH₂), with n=0 to 10-   —(CH₂)_(n)—Si(C₂H₅)(OC(CH₃)═CH₂), with n=0 to 10-   —(CH₂)_(n)—Si(OC₂H₅)(OC(CH₃)═CH₂)₂, with n=0 to 10-   —(CH₂)_(n)—Si(OC₂H₅)₂(OC(CH₃═CH₂), with n=0 to 10-   —(CH₂)_(n)—Si(OC₂H₅)₂(OC(CH₃)═CH₂) with n=0 to 10-   —(CH₂)_(n)—Si(C₆H₅)(OC₂H₅)₃, with n=0 to 10-   —(CH₂)_(n)—Si(C₆H₅)(OCH₃)₂, with n=0 to 10-   —(CH₂)_(n)—Si(C₆H₅)(OCH₃)(OC2H₅) with n=0 to 10-   —(CH₂)_(n)—Si(C₆H₅)(OC(CH₃)═CH₂)₂, with n=0 to 10.

The silanes according to the invention are stable compounds and can beprocessed either alone or together with other hydrolyzable, condensableand/or polymerizable components to produce silicic acid polycondensatesor silicic acid heteropolycondensates, the definitive curing of whichtakes place by polymerization of the C═C double bonds.

The silanes according to the invention can however also be processedalone or together with other hydrolyzable, condensable and/orpolymerizable components to produce polymerisates which can be hardenedby subsequent hydrolytic condensation.

A large number of silicic acid (hetero)polycondensates which aremodified with organic groups, and processes for their preparation (forexample starting from hydrolytically condensable organosilanes using thesol-gel process), are known. Such condensates are used, as alreadymentioned at the start, for the most varied purposes, for example asmoulding compounds or as lacquers for coverings. Due to the manydifferent application possibilities of this class of substance there ishowever also a constant need for modification of the already knowncondensates, on the one hand to thereby develop new application fieldsand on the other hand to optimize still further their properties forcertain application purposes.

The silanes according to the invention can be hydrolyzed and condensedin a basic or acid medium without a resulting linking of the C═C doublebonds. It is thereby possible to incorporate the silanes according tothe invention into an inorganic-organic network by hydrolyticcondensation. The silanes according to the invention containhydrolyzable groups X, for example alkoxy groups, so that an inorganicnetwork (Si—O—Si units) can thus be built up, while the C═C double bondscontained in radical B can be polymerized accompanied by theconstruction of an organic network. It is thereby possible to replaceorganically modified, hydrolyzable and condensable silanes in coating,filling, adhesion and sealing compounds, in moulded bodies and embeddingmaterials according to the state of the art by the silanes according tothe invention.

In order to construct the inorganic network, the silanes according tothe invention are hydrolyzed and polycondensed, optionally with theaddition of other cocondensable components. The polycondensationpreferably takes place according to the sol-gel process, as describedfor example in DE-A-2 758 414, DE-A-2 758 415, DE-A-3 011 761, DE-A-3826 715 and DE-A-3 835 968.

In order to construct the organic network, the silanes according to theinvention are polymerized and polycondensed optionally with the additionof other copolymerizable components. The polymerization can for examplebe thermal, redox-induced, covalent-nucleophilic and/or photochemicalusing methods such as are described for example in DE-A-3 143 820,DE-A-3 826 715 and DE-A-3 835 968.

As further polymerizable components, compounds can be added which can beradically and/or ionically polymerized. Radically polymerizablecompounds which can be added are for example those with C═C doublebonds, such as acrylates, vinyl cyclopropanes or methacrylates, thepolymerization taking place via the C═C double bonds, optionally withthe incorporation of the ring. Ionically polymerizable compounds whichcan be added contain for example ring systems which can be polymerizedcationically in ring-opening manner, such as spiroorthoesters,spiroorthocarbonates, bicyclic spiroorthoesters, mono- or oligoepoxidesor oxetanes or spirosilanes, such as are known from DE-C4 125 201.

However, compounds can also be added which can be both ionically andradically polymerized, such as methacryloyl-spiroorthoesters. These canbe radically polymerized via the C═C double bond and cationicallyaccompanied by ring opening. The preparation of these systems isdescribed for example in Journal f. prakt. Chemie, Vol. 330, No. 2,1988, pp. 316-318. Furthermore the silanes according to the inventioncan be used in systems such as are described for example in DE-A4 405261.

Furthermore it is possible to add other known, silane-bound cyclicsystems which can be jointly polymerized. Such systems are for examplethose which contain epoxides. Such systems are described for example inthe preparation of the spirosilanes of DE-C-4 125 201.

The silanes according to the invention represent highly reactive systemswhich lead to poly(hetero)condensates, which for example during UVirradiation lead within a very short time to mechanically stablecoverings or moulded or filling bodies. The silanes according to theinvention can be prepared via simple addition reactions and can containa variable number of reactive groups of different functionality throughsuitable selection of the starting compounds.

In the presence of two or more C═C double bonds in the radical B thedevelopment of a three-dimensional, organic network is possible. Themechanical properties (e.g. flexibility) and the physical-chemicalproperties (e.g. adsorption, refractive index, adhesion) of thepoly(hetero)condensates can be influenced via the distance between theSi atom and the radical B, i.e. via the chain length, and via thepresence of further functional groups in this chain. Through thedevelopment of an inorganic network, silicon- or glass-like propertiesof the poly(hetero)condensates can be set according to the type andnumber of the hydrolyzable groups (e.g. alkoxy groups).

The silanes according to the invention have relatively high molecularweights and consequently a reduced volatility vis-á-vis pure(meth)acrylate monomers, so that the toxic danger during the processingand application is less. During the inorganic and/or organiccrosslinking, polysiloxanes with an again reduced volatility form whichthus completely remove the toxicity problem of the acrylate components.

If the possible variations of the cocondensable and copolymerizablecomponents are then also taken into account, it becomes clear that, viathe silanes according to the invention, silicic acid(hetero)polycondensates are made available which can be adapted in manyways to given application fields and can therefore be used in all fieldsin which silicic acid (hetero)polycondensates have already been used,but also open up new application possibilities, for example in the fieldof optics, electronics, medicine, in particular dentistry,optoelectronics and packaging products for foodstuffs.

The silanes according to the invention can be used either as such or incompositions which additionally contain additives suited to theapplication purpose, for example customary lacquer additives, solvents,fillers, photoinitiators, thermal initiators, flow agents and pigments.

The silanes according to the invention or the compositions containingsilanes are suitable for example for the preparation of coating, fillingor bulk materials, of adhesives and injection-moulding compounds, offibres, particles, films, adhesion promoters, impression compounds andembedding materials.

Coatings and moulded bodies from the silanes according to the inventionhave the advantage that they can be photochemically structured. Specialapplication fields are for example the coating of substrates from metal,plastic, paper, ceramics (by immersion, pouring, painting, spraying,electrostatic spraying, electroimmersion varnishing), use for optical,optoelectric or electronic components, the production of fillers, theproduction of scratch-resistant, wear-resistant corrosion-protectioncoatings of moulded bodies, for example by injection moulding, mouldcasting, pressing, rapid prototyping or extrusion, and the production ofcomposites, for example with fibres, fillers or woven fabrics.

In addition to the silanes of formula I according to the inventionfurther hydrolytically condensable compounds of silicon, boron,aluminium, phosphorous, tin, lead, the transition metals, thelanthanides or the actinides can also be used. These compounds can beused either as such or already in precondensed form for the preparationof the polycondensates. It is preferred if at least 10 mol-%, inparticular at least 80 mol-% and specially at least 90 mol-%, based onmonomeric compounds, of the starting materials used for the preparationof the silicic acid (hetero)polycondensates are silicon compounds.

It is likewise preferred if at least 5 mol-%, for example 25 to 100mol-%, in particular 50 to 100 mol-%, and specially 75 to 100 mol-%, ofthe silicic acid (hetero)polycondensates, each based on monomericcompounds, are based on one or more of the silanes according to theinvention.

Of the hydrolytically condensable silicon compounds, different from thesilanes of general formula I, which can optionally be used, those of thegeneral formula VI are particularly preferred:R_(a)(R¹⁰Z′)_(f)SiX_(4-(e+f))  (VI)in which the individual radicals R, R¹⁰, X and Z′ are the same ordifferent, the radicals R and X are as defined above and the radicalsR¹⁰ and Z′ and the indices e and f have the following meaning:

-   R¹⁰=alkylene or alkenylene, these radicals being able to be    interrupted by oxygen or sulphur atoms or —NH groups;-   Z′=halogen or an optionally substituted amino, amide, aldehyde,    alkylcarbonyl, carboxy, mercapto, cyano, alkoxy, alkoxycarbonyl,    sulfonic acid, phosphoric acid, acryloxy, methacryloxy, epoxy or    vinyl group;-   e=0,1,2 or 3;-   f=0,1,2 or 3, with e+f=1,2 or 3.

Such silanes are described for example in DE-C-34 07 087.

Special examples for hydrolytically condensable silanes of the generalformula VI are:

-   CH₃—Si—Cl₃, CH₃—Si—(OC₂H₅)₃, C₂H₅—Si—Cl₃, C₂H₅—Si—(C₂H₅)₃,    CH₂═CH—Si—(OC₂H₅)₃, CH₂═CH—Si(OC₂H₄OCH₃)₃, (CH₃)₂—Si—Cl₂,    CH₂═CH—Si—(OOCCH₃)₃, (CH₃)₂—Si—(OC₂H₅)₂, (C₂H₅)₃—Si—Cl,    (C₂H₅)₂—Si—(OC₂H₅)₂, (CH₃)₂(CH₂═CH)—Si—Cl₂, (CH₃)₃—Si—Cl,    (t-C₄H₉)(CH₃)₂—Si—Cl, (CH₃O)₃—Si—C₃H₅—NH—C₂H₄—NH—C₂H₄—NH₂,    (CH₃O)₃—Si—C₃H₆—SH, (CH₃O)₃—Si—C₃H₆—NH—C₂H₄—N H₂,    (CH₃O)₃—Si—C₃H₆—Cl, (CH₃O)₃—Si—C₃H₅—O—C(O)—C(CH₃)═CH₂,    (CH₃)₂(CH₂═CH—CH₂)—Si—Cl, (C₂H₅O)₃—Si—C₃H₆—NH₂, (C₂H₅O)₃—Si—C₃H₆CN,

The silanes according to the invention need not necessarily be speciallyisolated for the further processing to poly(hetero)condensates. It isalso possible to prepare these silanes in a one-pot process first andthen optionally after adding further hydrolyzable compoundshydrolytically condense them.

Of the hydrolytically condensable silicon compounds, different from thesilanes of general formula I, which can optionally also be used, thoseof the general formula VIII are likewise particularly preferred:Y_(n)SiX_(m)R_(4-(n+m))  (VIII)in which the individual radicals X, Y and R are in each case the same ordifferent and X and R have the above, and Y, n and m the following,meaning:

-   Y+a substituent, which contains a substituted or unsubstituted    1,4,6-trioxaspiro-[4,4]-nonane radical;-   n=1,2 or 3;-   m=1,3 or 3, or with m+n≦4.

These spirosilanes can be hydrolyzed via the radicals X and polymerizedvia the radicals Y and are described in great detail in DE-C4 125 201.

Of the hydrolytically condensable silicon compounds, different from thesilanes of general formula I, which can optionally be used, those of thegeneral formula IX are likewise preferred:G{A—(Z)_(d)—R²⁰(R²¹)—R′—SiX_(a)R_(b)}_(c)  (IX)in which the radicals X, R and R′ have the above meaning and the otherradicals and indices have the following meaning:

G = a mono- to tetravalent, straight-chained or branched organic radi-cal with at least one C═C double bond and 4 to 50 carbon atoms; A = O, Sor NH for d = 1 and Z = CO and R²⁰ = alkylene, arylene oralkylenearylene in each case with 1 to 10 carbon atoms, these radicalsbeing able to be interrupted by oxygen and sulphur atoms or by aminogroups, and R²¹ = COOH; or A = O, S or NH for d = 1 and Z = CO and R²⁰ =alkylene, arylene or alkylenearylene in each case with 1 to 10 carbonatoms, these radicals being able to be interrupted by oxygen and sulphuratoms or by amino groups, and R²¹ = H; or A = O, S, NH or COO for d = 1and Z = CHR, with R equal to H, alkyl, aryl or alkylaryl, and R²⁰ =alkylene, arylene or alkylenearylene in each case with 1 to 10 carbonatoms, these radicals each being able to be interrupted by oxygen andsulphur atoms or by amino groups, and R²¹ = OH; or A = O, S, NH or COOfor d = 0 and R²⁰ = alkylene, arylene or alkylenearylene in each casewith 1 to 10 carbon atoms, these radicals being able to be interruptedby oxygen and sulphur atoms or by amino groups, and R²¹ = OH; or A = Sfor d = 1 and Z = CO and R²⁰ = N and R²¹ = H; a = 1, 2 or 3; b = 0, 1 or2; a + b = 3; c = 1, 2, 3 or 4; d = 0 or 1.

The silanes of formula IX can be polymerized via the radicals G andhydrolyzed via the radicals X. An inorganic network with Si—O—Si unitscan be constructed via the hydrolyzable groups, while the double bondscontained in the radical G polymerize accompanied by the construction ofan organic network.

For a=2 or b=2 the radicals X and R can in each case have the same or adifferent meaning.

Of the optionally used hydrolyzable aluminium compounds, those areparticularly preferred which have the general formula AIR°₃ in which theradicals R°, which can be the same or different, are selected fromhalogen, alkoxy, alkoxycarbonyl and hydroxy. With regard to the moredetailed (preferred) definitions of these radicals, reference can bemade to the statements in connection with the suitable hydrolyzablesilicon compounds. The just-named groups can also be replaced completelyor partly by chelate ligands (for example acetylacetone or aceto aceticacid ester, acetic acid).

Particularly preferred aluminium compounds are aluminium alkoxides andhalides. In this connection the following can be named as specificexamples:

-   Al(OCH₃)₃, Al(OC₂H₅)₃, Al(O-n-C₃H₇)₃, Al(O-i-C₃H₇)₃, Al(OC₄H₉)₃,    Al(O-i-C₄H₉)₃, Al(O-s-C₄H₉)₃, AlCl₃, AlCl—(OH)₂.

Compounds which are liquid at room temperature such as for examplealuminium-sec.-butylate and aluminium-isopropylate, are particularlypreferred.

Suitable hydrolyzable titanium or zirconium compounds, which canoptionally be used, are those of the general formula MX_(y)R_(z), inwhich M stands for Ti or Zr, y is an integer from 1 to 4, in particular2 to 4, z stands for 0,1,2 or 3, preferably for 0, 1 or 2, and X and Rare as defined in the case of the general formula I. This also appliesto the preferred meanings. It is particularly preferred if y is equal to4.

As in the case of the above Al compounds, complexed Ti or Zr compoundscan also be used. Additional preferred complexing agents here areacrylic acid and methacrylic acid.

Specific examples of Zr and Ti compounds are the following:

-   TiCl₄, Ti(OC₂H₅)₄, Ti(OC₃H₇)₄, Ti(O-i-C₃H₇)₄, Ti(OC₄H₉)₄,    Ti(2-ethylhexoxy)₄, ZrCl₄, Zr(OC₂H₅)₄, Zr—(OC₃H₇)₄, Zr(O-i-C₃H₇)₄,    Zr(OC₄H₉)₄, Zr(2-ethylhexoxy)₄, ZrOCl₂.

Further hydrolyzable compounds which can be used for the preparation ofthe polyheterocondensates are for example boron trihalides and boricacid esters, such as BCl₃, B(OCH₃)₃ and B(OC₂H₅)₃, stannous tetrahalidesand stannous tetraalkoxides, such as SnCl₄ and Sn(OCH₃)₄, and vanadylcompounds, such as VOCl₃ and VO(OCH₃)₃.

As already mentioned, the preparation of the poly(hetero)condensates cantake place in a manner customary in this field. If silicon compounds areused practically exclusively, the hydrolytic condensation can in mostcases take place by adding the necessary water directly to the siliconcompounds to be hydrolyzed, which are present either as such ordissolved in a suitable solvent, at room temperature or accompanied byslight cooling (preferably while stirring and in the presence of ahydrolysis and condensation catalyst) and thereupon stirring theresulting mixture for some time (one to several hours).

In the presence of reactive compounds of Al, Ti or Zr, a step-by-stepaddition of the water is recommended as a rule. Regardless of thereactivity of the compounds present, the hydrolysis takes place as arule at temperatures between −20 and 130° C., preferably between 0 and30° C. or the boiling point of the optionally used solvent. As alreadypointed out, the best method of adding water depends above all on thereactivity of the starting compounds used. Thus, for example, thedissolved starting compounds can be dropped slowly to an excess ofwater, or water is added in a portion or portionwise to the optionallydissolved starting compounds. It can also be useful not to add the wateras such, but to introduce it into the reaction system with the help ofhydrous organic or inorganic systems. In many cases, the introduction ofthe quantity of water into the reaction mixture with the help ofmoisture-laden absorbents, for example molecular sieves and hydrousorganic solvents, for example 80% ethanol, has proved particularlysuitable. The addition of water can however also take place via achemical reaction in which water is released in the course of thereaction. Examples of this are esterifications.

If a solvent is used, consideration is also given, in addition to thelow aliphatic alcohols (for example ethanol or i-propanol), to ketones,preferably low dialkylketones, such as acetone or methyl isobutylketone, ethers, preferably low dialkylethers such as diethylether ordibuylether, THF, amides, esters, in particular acetic acid ethyl ester,dimethylformamide, amines, in particular triethylamine, and theirmixtures.

If spirosilanes are used for the preparation of thepoly(hetero)condensates then the hydrolysis is preferably carried out ina medium which is basic with regard to the spirosilanes. This isproduced either by a basic solvent, such as for example triethylamine,or by adding basic hydrolysis and condensation catalysts, such as KOH,methylimidazole.

The starting compounds need not necessarily already all be present atthe start of the hydrolysis (polycondensation), but in certain cases itcan even prove to be advantageous if only some of these compounds arefirstly brought into contact with water and the remaining compounds areadded later.

In order to avoid precipitations during hydrolysis and polycondensationas much as possible, in particular when using hydrolyzable compoundsdifferent from silicon compounds, the addition of water can be carriedout in several steps, for example in three steps. In the first step, atenth to a twentieth of the amount of water required for hydrolysis canfor example be added. After brief stirring, a fifth to a tenth of therequired amount of water can be added, and after further brief stirring,the remainder can finally be added.

The condensation time is geared to the starting components in each caseand their proportions, to the optionally used catalyst, to the reactiontemperature, etc. In general, the polycondensation takes place undernormal pressure, but can also be carried out at increased or reducedpressure.

The thus-obtained poly(hetero)condensate can be processed further eitheras such or after partial or almost complete removal of the solvent used.In some cases it can prove to be advantageous in the product obtainedafter the polycondensation to replace the excess water and the formedand optionally additionally used solvent with another solvent, in orderto stabilize the poly(hetero)condensate. For this purpose, the reactionmixture can be thickened for example under vacuum at a slightlyincreased temperature to the point where it can still be taken upproblem-free by another solvent.

If these poly(hetero)condensates are to be used as lacquers for coating(for example of plastics such as PVC, PC, PMMA, PE, PS of glass, paper,wood, ceramics, metal etc), then customary lacquer additives, such ascolouring agents (pigments or dyes), fillers, oxidation inhibitors,flame-protection products, flow agents, UV adsorbers, stabilizers orsimilar, can optionally also be added to them at the latest before use.Additives to increase conductivity (for example graphite powder, silverpowder) also merit a mention in connection with this. In the case of useas moulding compound, the addition of inorganic and/or organic fillers,such as organic and inorganic particles, (glass) fibres, minerals, canin particular be considered.

The final curing of the poly(hetero)condensates takes place after theaddition of suitable initiators, and is thermal, redox-induced,covalent-nucleophilic or photochemical, several curing mechanisms alsobeing able to operate in parallel and/or in sequence. In the course ofthe polymerization, the C═C double bonds are linked and the organicnetwork is constructed. Due to the relatively high molecular weights ofthe silanes according to the invention, these experience only a slightvolume shrinkage during curing.

It is also possible to add further ionically and/or radicallypolymerizable components to the poly(hetero)condensate before the finalcuring, i.e. before polymerization. Radically polymerizable compoundswhich can be added are for example those with C═C double bonds, such assay acrylates or methacrylates, the polymerization taking place via theC═C double bonds. Ionically polymerizable compounds which can be addedcontain for example ring systems which can be polymerized cationicallyin ring-opening manner, such as say spiroorthoesters,spiroorthocarbonates, bicyclic spiroorthoesters, mono- or oligoepoxidesor spirosilanes of the general formula VIII. However, compounds can alsobe added which can be polymerized both cationically and radically, suchas for example methacryloyl spiroorthoesters. These can be polymerizedradically via the C═C double bond and cationically accompanied by ringopening. These systems are described for example in the Journal f.prakt. Chemie., Volume 330, No. 2, 1988, pp. 316-318 or in the Journalof Polymer Science: Part C, Polymer Letters, Vol. 26, pp. 517-520(1988).

If the curing of the poly(hetero)condensate takes place photochemically,photoinitiators are added to the latter, thermal initiators in the caseof thermal curing, and starter-activator systems in the case ofredox-induced curing.

The initiator can be added in normal amounts. Thus, for example, therecan be added to a mixture which contains 30 to 50 wt.-% solids(polycondensate), initiators in a quantity of for example 0.5 to 5wt.-%, in particular from 1 to 3 wt.-%, relative to the mixture.

If, for the preparation of the poly(hetero)condensates, in addition tothe silanes according to the invention, further components are usedwhich contain reactive double bonds, such as silanes according to thegeneral formula VII, then a polymerization can likewise take place viathese double bonds which can be thermal and/or photochemical and/orcovalent-nucleophilic and/or redox-initiated.

There can be used as photoinitiators for example those which arecommercially available. Examples of these are Irgacure 184(1-hydroxycyclohexylphenylketone), Irgacure 500(1-hydroxycyclohexylphenylketone-benzophenone), and other Irgacure-typephotoinitiators which can be obtained from Ciba-Geigy: Darocure 1173,1116, 1398, 1174 and 1020 (obtainable from Merck), benzophenone,2-chlorothioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone,benzoin, 4,4′-dimethoxybenzoin etc. If the curing takes place withvisible light, such as for example in dentistry, camphorquinone forexample can be used as initiator.

Coming into consideration as thermal initiators are in particularorganic peroxides in the form of diacylperoxides, peroxydicarbonates,alkylperesters, dialkylperoxides, perketals, ketone peroxides andalkylhydroperoxides. Specific and preferred examples of thermalinitiators are dibenzoyl peroxide, t-butylperbenzoate andazobisisobutyronitrile.

Starter activator systems customary for this purpose can be used, suchas for example aromatic amines (for exampleN,N-bis-(2-hydroxyethyl)-p-toluidine) as activators, or dibenzoylperoxide for example as starters, the curing time being able to be setaccording to the respective use via their concentration and/or theirconcentration ratio. Further amines can be found for example in DE-A4310 733.

In the case of covalent-nucleophilic curing, compounds with at least oneamino group for example are added as initiators. Suitable amines can befound for example in DE-A4 405 261.

A lacquer (poly(hetero)condensate) provided with an initiator on thebasis of the silanes according to the invention can be used for coatingsof substrates. Customary coating processes can be used for this coating,for example dipping, flooding, pouring, centrifuging, rolling, spraying,painting, electrostatic spraying and electrodip-coating. It should alsobe mentioned here that the lacquer need not necessarily contain solvent.In particular when using starting substances (silanes) with two alkoxygroups at the Si atom, it is also possible to proceed without theaddition of solvents.

Before curing, the applied lacquer is preferably left to dry.Afterwards, depending on the type of initiator, it can be cured in amanner known per se by redox-initiation, thermally or photochemically.Naturally, combinations of curing methods are also possible.

If the curing of the applied lacquer takes place by irradiation it canprove advantageous to carry out a thermal curing after the radiationcuring, in particular to remove solvent which is still present or toincorporate still more reactive groups into the curing.

Although polymerizable groups are already present in thepoly(hetero)condensates on the basis of the silanes according to theinvention, it can prove advantageous in certain cases to add still morecompounds (preferably of a purely organic nature) with for exampleunsaturated groups to these condensates before or during their furtherprocessing (curing).

Preferred examples of such compounds are acrylic acid and methacrylicacid as well as compounds derived therefrom, in particular esters ofpreferably monohydric alcohols (for example C₁₋₄ alkanols),(meth)acrylonitrile, styrene and mixtures of same. In the case of usingthe poly(hetero)condensates for the preparation of coating lacquers,such compounds can act simultaneously as solvents and/or dilutingagents.

The preparation of moulded bodies or moulding compounds frompoly(hetero)condensates on the basis of silanes according to theinvention can take place with every method customary in this field, forexample by injection moulding, mould casting, extrusion. Thepoly(hetero)condensates based on the silanes according to the inventionare also suitable for the preparation of composite materials (forexample with glass-fibre reinforcement).

With the multifunctional silanes according to the invention, startingcompounds are available which make possible the preparation ofinorganic-organic composite polymers having the most varied propertieswhich can be set within wide ranges, or the modification of existingcomposite polymers. The use of such materials extends to the most variedpurposes and among others to their use as bulk materials, composites,adhesives, casting compounds, coating materials, adhesion promoters, andbinders for ceramic particles (ceramic shaping processes), for thepreparation or priming of fillers and fibres, grinding wheels, for usein the reaction extruder, etc. For organic polymerization,photochemically, thermally and chemically (2-component, anaerobic, redoxetc) induced conversion can be considered. The combination ofself-curing with for example photo-induced or thermal curing is likewisepossible.

The invention is explained in the following in more detail by examples,without it thereby being limited in any way.

PREPARATION EXAMPLE 1 Preparation of the Hydrosilylation Product of1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane withAllyloxyethyl Methacrylate

1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane was obtained from1,1,3,3-tetramethyldisiloxane and vinyltrimethoxysilane according to J.V. Crivello and Daoshen Bi (J. Polym. Sci A 31 (1993) 3121).

14.1 g (0.05 M) 1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxaneare heated to 100° C. in 100 ml dry toluene under inert gas with 5 mg ofpolymer-bound Wilkinson catalyst and 8.5 g (0.05 M) of allyloxyethylmethacrylate. After four hours the allyl and SiH absorptions in the¹H-NMR spectrum have disappeared. The reaction mixture is left to cool,filtered from the catalyst and the solvent drawn off under reducedpressure.

A colourless, low-viscosity oil remains. The yield is 98% of thetheoretical value.

PREPARATION EXAMPLE 2 Hydrolysis and Condensation of the Product fromPreparation Example 1

9.1 g (0.02 mol) of the compound from preparation example 1 are stirredwith 1.1 g (0.06 mol) water (added as 0.1 M HCl) in 50 ml acetic esterfor 24 hours at 40° C. The reaction mixture is then neutralized withNaHCO₃ solution, dried and freed of solvent. The condensate is capableof flowing and is obtained in a yield of 96% of the theoretical value.

PREPARATION EXAMPLE 3 Co-Hydrolysis of the Product from Example 1 withTMOS

9.1 g (0.02 mol) of the compound from preparation example 1 are reactedwith 0.76 g (0.005 mol) tetramethylorthosilicate (TMOS) and agitated in50 ml acetic ester with 1.4 g (0.08 mol) water (added as 0.1 M HCl) for36 hours at 36° C. The solution is neutralized using NaHCO₃ solution,dried and freed of the solvent. The yield of viscose condensate is 95%of the theoretical value.

PREPARATION EXAMPLE 4 Preparation of the Hydrosilylation Product from1-(trimethoxysilylethyl)-1,1,4,4-tetramethyldisilabutane and glyceroldimethyacrylate-allylether

1-(trimethoxysilylethyl)-1,1,4,4-tetramethyldisilabutane is preparedanalogously to 1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane inpreparation example 1 from 1,2-bisdimethylsilylethane. A colourless,hydrolysis-labile oil is obtained in a yield of 54% of the theoreticalvalue.

5.9 g (0.02 M) 1-(trimethoxysilylethyl)-1,1,4,4-tetramethyldisilabutaneare dissolved in 100 ml dry toluene and reacted with 5 mg Deloxane Ptcatalyst and under reflux with 5.4 g (0.02 M) glyceroldimethyacrylate-allylether. After the heat effect has faded, a sample istaken and the SiH vibration at 2160 cm⁻¹ tested by means of IR. Whenthis has disappeared, the reaction mixture is filtered off from thecatalyst and the solvent distilled off. The adduct is obtained as acolourless, hydrolysis-labile oil in a yield of 94% of the theoreticalvalue.

PREPARATION EXAMPLE 5 Hydrolysis and Condensation of the Product fromPreparation Example 4

11.3 g (0.02 mol) of the compound from example 4 are agitated with 1.1 g(0.06 mol) water (added as 0.1 M HCl) in 50 ml acetic ester for 24 hoursat 40° C. The reaction mixture is then neutralized with NaHCO₃ solution,dried and freed of solvent. The condensate is capable of flowing and isobtained in a yield of 97% of the theoretical value.

PREPARATION EXAMPLE 6 Co-Hydrolysis of the Product from PreparationExample 4 with TMOS

11.3 g (0.02 mol) of the compound from example 4 are reacted with 0.8 g(0.005 mol) tetramethylorthosilicate and agitated in 50 ml acetic esterwith 1.4 g (0.08 mol) water (added as 0.1 M HCl) for 36 hours at 36° C.The solution is neutralized by means of NaHCO₃ solution, dried and freedof solvent. The yield of viscose condensate is 96% of the theoreticalvalue.

PREPARATION EXAMPLE 7 Preparation of the Hydrosilylation Product from1-(trimethoxysilylethyl)-1-methyl-1-phenylsilane and glyceroldimethacrylate-allylether

1-(trimethoxysilylethyl)-1-methyl-1-phenylsilane is prepared analogouslyto 1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane in preparationexample 1 from 1-methyl-1-phenylsilane. It is obtained as a colourless,hydrolysis-labile oil in a yield of 69% of the theoretical value.

13.5 g (0.05 mol) 1-(trimethoxysilylethyl)-1-methyl-1-phenylsilane aredissolved in 100 ml dry toluene and reacted with 5 mg Deloxane Ptcatalyst and under reflux with 13.4 g (0.05 mol) glyceroldimethacrylate-allylether. After the heat effect has faded, a sample istaken and the SiH vibration at 2160 cm⁻¹ tested by means of IR. If thishas disappeared, the reaction mixture is filtered off from the catalystand the solvent distilled off. The adduct is obtained as a colourless,hydrolysis-labile oil in a yield of 94% of the theoretical value.

PREPARATION EXAMPLE 8 Hydrolysis and Condensation of the Product fromPreparation Example 7

10.8 g (0.02 mol) of the compound from preparation example 7 areagitated with 1.1 g (0.06 mol) water (added as 0.1 M HCl) in 50 mlacetic ester for 24 hours at 40° C. The reaction mixture is thenneutralized with NaHCO₃ solution, dried and freed of solvent. Thecondensate is capable of flowing and is obtained in a yield of 97% ofthe theoretical value.

PREPARATION EXAMPLE 9 Co-Hydrolysis of the Product from PreparationExample 7 with TMOS

10.8 g (0.02 mol) of the compound from preparation example 7 are reactedwith 0.8 g (0.005 mol) tetramethylorthosilicate and agitated in 50 mlacetic ester with 1.4 g (0.08 mol) water (added as 0.1 M HCl) for 36hours at 36° C. The solution is neutralized by means of NaHCO₃ solution,dried and freed of solvent. The yield of viscose condensate is 96% ofthe theoretical value.

PREPARATION EXAMPLE 10 Preparation of the Hydrosilylation Product from1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane with VinylNorbornene

1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane was obtained from1,1,3,3-tetramethyldisiloxane and vinyltrimethoxysilane according to J.V. Crivello and Daoshen Bi (J. Polym. Sci A 31 (1993) 3121).

14.1 g (0.05 mol) 1-(trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxaneare heated to 100° C. in 100 ml dry toluene under inert gas with 5 mgpolymer-bound Wilkinson catalyst and 6.0 g (0.05 mol) vinyl norbornene.After four hours, the vinyl absorptions in the ¹H-NMR spectrum havevanished. The reaction mixture is left to cool, filtered from thecatalyst and the solvent drawn off under reduced pressure.

A colourless, low-viscosity oil remains. The yield is 98% of thetheoretical value.

PREPARATION EXAMPLE 11 Hydrolysis and Condensation of the Product fromPreparation Example 10

8.1 g (0.02 mol) of the compound from preparation example 10 areagitated with 1.1 g (0.06 mol) water (added as 0.1 M HCl) in 50 mlacetic ester for 24 hours at 40° C. The reaction mixture is thenneutralized with NaHCO₃ solution, dried and freed of solvent. Thecondensate is capable of flowing and is obtained in a yield of 96% ofthe theoretical value.

PREPARATION EXAMPLE 12 Co-Hydrolysis of the Product from PreparationExample 10 with TMOS

8.1 g (0.02 mol) of the compound from preparation example 10 are mixedwith 0.8 g (0.05 mol) tetramethylorthosilicate and agitated in 50 mlacetic ester with 1.4 g (0.08 mol) water (added as 0.1 M HCl) for 36hours at 36° C. The solution is neutralized by means of NaHCO₃ solution,dried and freed of solvent. The yield of viscose condensate is 95% ofthe theoretical value.

PREPARATION EXAMPLE 13

Preparation of the Hydrosilylation Product of1-(methyldimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane withTrimethylolpropanetriacrylate

1-(methyldimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane was obtainedanalogously to J. V. Crivello and Daoshen Bi (J. Polym. Sci A 31 (1993)3121) from 1,1,3,3-tetramethyldisiloxane and vinylmethyldimethoxysilanein a yield of 67% of the theoretical value.

8.0 g (0.03 mol)1-(methyldimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane are heatedto 100° C. in 100 ml dry toluene under inert gas with 5 mg polymer-boundWilkinson catalyst and 14.4 g (0.05 mol) trimethylolpropanetriacrylate.After four hours, the vinyl absorptions in the ¹H-NMR spectrum havevanished. The reaction mixture is left to cool, filtered off from thecatalyst and the solvent drawn off under reduced pressure.

A colourless, low-viscosity oil remains. The yield is 98% of thetheoretical value.

PREPARATION EXAMPLE 14 Hydrolysis and Condensation of the Product fromPreparation Example 13

7.5 g (0.01 mol, relative to the dimethoxysilyl content) of the compoundfrom preparation example 13 are agitated with 0.4 g (0.02 mol) water(added as 0.1 M HCl) in 50 ml acetic ester for 24 hours at 40° C. Thereaction mixture is then neutralized with NaHCO₃ solution, dried andfreed of solvent. The condensate is capable of flowing and is obtainedin a yield of 96% of the theoretical value.

PREPARATION EXAMPLE 15 Co-Hydrolysis of the Product from PreparationExample 13 with TMOS

7.5 g (0.01 mol relative to the dimethoxysilyl content) of the compoundfrom preparation example 13 are mixed with 0.005 moltetramethylorthosilicate and agitated in 50 ml acetic ester with 0.7 g(0.04 mol) water (added as 0.1 M HCl) for 36 hours at 36° C. Thesolution is neutralized by means of NaHCO₃ solution, dried and freed ofsolvent. The yield of viscose condensate is 95% of the theoreticalvalue.

1. A method for preparing silicic acid polycondensates or silicic acidheteropolycondensates comprising hydrolytically condensing one or morehydrolytically condensable compounds of silicon, said hydrolyticallycondensable compound optionally comprising one or more elements selectedfrom the group consisting of B, AI, P, Sn, Pb, the transition metals,the lanthanides and the actinides, said condensable compound optionallycomprising precondensates of the compound; the reaction optionallycomprising one or more of (i) a catalyst, (ii) a solvent, (iii) anionically polymerizable compound and (iv) a free-radical polymerizablecompound; wherein 5 to 100% mol % based on monomeric compounds of thehydrolytically condensable compounds are silanes of the general formulaI:B{(A)_(d)—R′—U—R′—SiX_(a)R_(b)}_(c)  (I) in which: B is a mono- totetravalent, straight-chained or branched organic radical with at leastone C═C double bond and 4 to 50 carbon atoms; X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″₂; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R′ is alkylene,alkenylene, arylene, arylenealkylene or alkylenearylene having 2 to 10carbon atoms, these radicals being able to be interrupted by oxygen andsulphur atoms or by amino groups; R′ is hydrogen, alkyl or aryl; U is aninorganically modified organic radical comprising a siloxane orcarbosiloxane framework having atoms that are silicon or germanium or acarbosilane framework having at least one atom that is silcon orgermanium, said framework having 1 to 15 C atoms and up to 5 additionalheteroatoms that are O, S or N; A is C(═O)O, OC(═O)O, C(═O), O, S,C(═O)NR″, OC(═O), or NR″(═O); a = 1, 2 or 3; b = 0, 1 or 2; a + b = 3; c= 1, 2, 3 or 4; and d = 0 or
 1.


2. The method of claim 1, wherein B is a mono- to tetravalent,straight-chained or branched organic radical with at least one C═Cdouble bond and 4 to 30 carbon atoms; X is hydrogen, halogen, hydroxy,alkoxy, acyloxy or alkylcarbonyl; R is alkyl, alkenyl or aryl; R′ isalkylene, alkenylene, arylene, arylenealkylene or alkylenearylene having2 to 5 carbon atoms, these radicals being able to be interrupted byoxygen and sulphur atoms or by amino groups; A is C(═O)O, OC(═O)O, C(O),0, OC(═O); U is an inorganically modified organic radical comprising asiloxane or carbosiloxane framework having atoms that are silicon orgermanium or a carbosilane framework having at least one atom that issilcon or germanium, said framework having 1 to 15 C atoms and up to 5additional heteroatoms that are O or N; a = 1, 2 or 3; b = 0, 1 or 2;a + b = 3; c = 1, 2, 3 or 4; and d = 0 or
 1.


3. The method according to claim 1, wherein the reaction mixture furthercomprises one or more compounds of the general formula VI, optionally inprecondensed form, as an additional hydrolytically condensable compoundof silicon:R_(e)(R¹⁰Z′)_(f)SiX_(4-(e+f))  (VI) in which X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″2; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R″ is hydrogen, alkyl oraryl; R¹⁰ is alkylene or alkenylene, these radicals being able to beinterrupted by oxygen or sulphur atoms or —NH groups; Z′ is halogen oran optionally substituted amino, amide, aldehyde, alkylcarbonyl,carboxy, mercapto, cyano, alkoxy, alkoxycarbonyl, sulfonic acid,phosphoric acid, acryloxy, methacryloxy, epoxy or vinyl group; e = 0, 1,2 or 3; and f = 0, 1, 2 or 3, with e + f = 1, 2 or
 3.


4. The method according to claim 3, in which X is hydrogen, halogen,hydroxy, alkoxy, acyloxy or alkylcarbonyl; and R is alkyl, alkenyl oraryl.
 5. The method according to claim 2, wherein the reaction mixturefurther comprises one or more compounds of the general formula VI,optionally in precondensed form, as an additional hydrolyticallycondensable compound of silicon:R_(e)(R¹⁰Z′)_(f)SiX_(4-(e+f))  (VI) in which X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″2; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R″ is hydrogen, alkyl oraryl; R¹⁰ is alkylene or alkenylene, these radicals being able to beinterrupted by oxygen or sulphur atoms or —NH groups; Z′ is halogen oran optionally substituted amino, amide, aldehyde, alkylcarbonyl,carboxy, mercapto, cyano, alkoxy, alkoxycarbonyl, sulfonic acid,phosphoric acid, acryloxy, methacryloxy, epoxy or vinyl group; e = 0, 1,2 or 3; and f = 0, 1, 2 or 3, with e + f = 1, 2 or
 3.


6. The method according to claim 5, in which X is hydrogen, halogen,hydroxy, alkoxy, acyloxy or alkylcarbonyl; and R is alkyl, alkenyl oraryl.
 7. The method according to claim 1, in which the reactioncomprises at least one compound the general formula VIII, optionally inprecondensed form, as an additional hydrolytically condensable compoundof silicon:Y_(n)SiX_(m)R_(4-(n+m))  (VIII) in which X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″2; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R″ is hydrogen, alkyl oraryl; Y is a substituent that comprises a substituted or unsubstituted1,4,6-trioxaspiro-[4,4]-nonane radical; n = 1, 2 or 3; and m = 1, 2 or3, and n + m ≦
 4.


8. The method according to claim 7, in which X = hydrogen, halogen,hydroxy, alkoxy, acyloxy or alkylcarbonyl; and R = alkyl, alkenyl oraryl.


9. The method according to claim 1, wherein one or more aluminium,titanium or zirconium compounds, soluble in the reaction medium, of theformula:AIR° or MX_(y)R_(z) are used, optionally in precondensed form, as anadditional hydrolytically condensable compound in which M is titanium orzirconium; the radicals R, R° and X are the same or different; R° ishalogen, hydroxy, alkoxy or acyloxy; y=1, 2, 3 or 4; z=0, 1, 2 or 3; andX is hydrogen, halogen, hydroxy, alkoxy, acyloxy, alkylcarbonyl,alkoxycarbonyl or NR″ 2; R is alkyl, alkenyl, aryl, alkylaryl orarylalkyl; and R″ is hydrogen, alkyl or aryl.
 10. The method accordingto claim 9, in which X is hydrogen, halogen, hydroxy, alkoxy, acyloxy oralkylcarbonyl; and R is alkyl, alkenyl or aryl.
 11. The method accordingto claim 10, in which y=2, 3 or
 4. 12. The method according to claim 9,in which z=0, 1 or
 2. 13. The method according to claim 12, in whichy=2, 3 or
 4. 14. The method according to claim 1, wherein one or moreinitiators are added to the polycondensate, and the polycondensate isthen cured thermally, photochemically, in a covalent-nucleophilic manneror by redox-induction.
 15. The process according to claim 1, wherein thereaction mixture further comprises one or more compounds of the generalformula IX, optionally in precondensed form, as at least one condensablecompound of silicon:G{A—(Z)_(d)—R²⁰(R²¹)—R′—SiX_(a)R_(b)}_(c)  (IX) in which: X is hydrogen,halogen, hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl orNR″₂; R is alkyl, alkenyl, aryl, alkylaryl or arylalkyl; R″ is hydrogen,alkyl or aryl; and G is a straight-chained or branched organic radicalwith at least one C═C double bond and 4 to 50 carbon atoms; d=1; A is O,S or NH; z is C═O; R²⁰ is alkylene, arylene or alkylenearylenecomprising 1 to 10 carbon atoms, and optionally interrupted by one ormore atom of oxygen or sulfur or by one or more amino group; R²¹ isCOOH; or G is a straight-chained or branched organic radical with atleast one C═C double bond and 4 to 50 carbon atoms; d=1 A is O, S, orNH; Z is C═O; R²⁰ is alkylene, arylene or alkylenearylene comprising 1to 10 carbon atoms, and optionally interrupted by one or more atom ofoxygen or sulfur or by one or more amino groups; R²¹ is H; or G is astraight-chained or branched organic radical with at least one C═Cdouble bond and 4 to 50 carbon atoms; d=0 A is O, S, NH or COO; R²⁰ isalkylene, arylene or alkylenearylene comprising 1 to 10 carbon atoms,and optionally interrupted by one or more atom of oxygen or sulfur or byone or more amino group; R²¹ is OH; or G is a straight-chained orbranched organic radical with at least one C═C double bond and 4 to 50carbon atoms; d=1; A is S; Z is C═O; R²⁰ is N; R²¹ is H; or G is astraight-chained or branched organic radical with at least one C═Cdouble bond and 4 to 50 carbon atoms; d=1; A is O, S, NH or COO; Z isCHR, with R being H, alkyl, or alkylaryl; R²⁰ is alkylene, arylene oralkylenearylene comprising 1 to 10 carbon atoms, and optionallyinterrupted by one or more atom of oxygen or sulfur or by one or moreamino group; R²¹ is OH; and a = 1, 2 or 3; b = 0, 1 or 2; a + b = 3; c =1, 2, 3 or
 4.


16. The method of claim 15, in which X = hydrogen, halogen, hydroxy,alkoxy, acyloxy or alkylcarbonyl; and R = alkyl, alkenyl or aryl.


17. A polymer made by the process of claim
 1. 18. A dental fillingmaterial, dental cement, dental crown, dental bridge, dental facingmaterial, dental lacquer, dental sealer, dental adhesion promoter,dental primer or dental bonder comprising a polymer made by the processof any one of claims 3-6.
 19. A method for preparing silicic acidpolycondensates or silicic acid heteropolycondensates comprisinghydrolytically condensing one or more hydrolytically condensablecompounds of silicon, said hydrolytically condensable compoundoptionally comprising one or more elements selected from the groupconsisting of B, AI, P, Sn, Pb, the transition metals, the lanthanidesand the actinides, said condensable compound optionally comprisingprecondensates of the compound; the reaction optionally comprising oneor more of (i) a catalyst, (ii) a solvent, (iii) an ionicallypolymerizable compound and (iv) a free-radical polymerizable compound;wherein 5 to 100% mol % based on monomeric compounds of thehydrolytically condensable compounds are silanes of the general formulaI:B{(A)_(d)—R′—U—R′—SiX_(a)R_(b)}_(c)  (I) in which: B is a mono- totetravalent, straight-chained or branched organic radical with at leastone C═C double bond and 4 to 50 carbon atoms; X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″2; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R′ is alkylene,alkenylene, arylene, arylenealkylene or alkylenearylene having 2 to 10carbon atoms, these radicals being able to be interrupted by oxygen andsulphur atoms or by amino groups; R″ is hydrogen, alkyl or aryl; U is aninorganically modified organic radical comprising a siloxane orcarbosiloxane framework having at least two atoms that are silicon orgermanium or a carbosilane framework having at least one atom that issilcon or germanium, said framework having 1 to 15 C atoms and up to 5additional heteroatoms that are O, S or N; A is C(═O)O, OC(═O)O, C(═O),O, S, C(═O)NR″, OC(═O), or NR″C(═O); a = 1, 2 or 3; b = 0, 1 or 2; a + b= 3; c = 1, 2, 3 or 4; and d = 0 or 1;

wherein an ionically polymerizable compound or a free-radicallypolymerizable compound is present in the reaction.
 20. A method forpreparing silicic acid polycondensates or silicic acidheteropolycondensates comprising hydrolytically condensing one or morehydrolytically condensable compounds of silicon, said hydrolyticallycondensable compound optionally comprising one or more elements selectedfrom the group consisting of B, AI, P, Sn, Pb, the transition metals,the lanthanides and the actinides, said condensable compound optionallycomprising precondensates of the compound; the reaction optionallycomprising one or more of (i) a catalyst, (ii) a solvent, (iii) anionically polymerizable compound and (iv) a free-radical polymerizablecompound; wherein 5 to 100% mol % based on monomeric compounds of thehydrolytically condensable compounds are silanes of the general formulaI:B{(A)_(d)—R′—U—R′—SiX_(a)R_(b)}_(c)  (I) in which: B is a mono- totetravalent, straight-chained or branched organic radical with at leastone C═C double bond and 4 to 30 carbon atoms; X is hydrogen, halogen,hydroxy, alkoxy, acyloxy or alkylcarbonyl; R is alkyl, alkenyl or aryl;R′ is alkylene, alkenylene, arylene, arylenealkylene or alkylenearylenehaving 2 to 5 carbon atoms, these radicals being able to be interruptedby oxygen and sulphur atoms or by amino groups; A is C(═O)O, OC(═O)O,C(O), O, OC(═O); U is an inorganically modified organic radicalcomprising a siloxane or carbosiloxane framework having two atoms thatare silicon or germanium or a carbosilane framework having at least oneatom that is silcon or germanium, said framework having 1 to 15 C atomsand up to 5 additional heteroatoms that are O or N; a = 1, 2 or 3; b =0, 1 or 2; a + b = 3; c = 1, 2, 3 or 4; and d = 0 or 1;

wherein an ionically polymerizable compound or a free-radicallypolymerizable compound is present in the reaction.
 21. A method forpreparing a polymer comprising radical polymerizing one or morecompounds that comprise at least one C═C double bond and optionallyother radically polymerizable compounds; the reaction mixture optionallyfurther comprising one or more ionically polymerizable compounds and theprocess optionally further comprising ionically polymerizing saidionically polymerizable compounds by one or more of heating, irradiatingthe reaction with electromagnetic radiation, a redox-induction or acovalent-nucleophilic reaction, the reaction mixture optionally furthercomprising one or more hydrolytically condensable compounds of siliconand optionally other elements selected from the group consisting of B,Al, Sn, Pb, the transition metals, the lanthanides and the actinides,and/or precondensates derived from said hydrolytically condensablecompounds and the process further optionally comprising hydrolyticallycondensing said hydrolytically condensable compounds of silicon; thereaction mixture still further optionally comprising one or moreinitiators and/or a solvent; wherein 5 to 100 mol % based on monomericcompounds are selected from condensates of silanes of formula I:B{(A)_(d)—R′—U—R′—SiX_(a)R_(b)}_(c)  (I) in which: B is a mono- totetravalent, straight-chained or branched organic radical with at leastone C═C double bond and 4 to 50 carbon atoms; X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″2; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R′ is alkylene,alkenylene, arylene, arylenealkylene or alkylenearylene having 2 to 10carbon atoms, these radicals being able to be interrupted by oxygen andsulphur atoms or by amino groups; R″ is hydrogen, alkyl or aryl; U is aninorganically modified organic radical comprising a siloxane orcarbosiloxane framework having two atoms that are silicon or germaniumor a carbosilane framework having at least one atom that is silcon orgermanium, said framework having 1 to 15 C atoms and up to 5 additionalheteroatoms that are O, S or N; A is C(═O)0, OC(═O)O, C(═O), O, S,C(═O)NR″, OC(═O), or NR″C(═O); a = 1, 2 or 3; b = 0, 1 or 2; a + b = 3;c = 1, 2, 3 or 4; and d = 0 or
 1.


22. The method of claim 21, wherein B is a mono- to tetravalent,straight-chained or branched organic radical with at least one C═Cdouble bond and 4 to 30 carbon atoms; X is hydrogen, halogen, hydroxy,alkoxy, acyloxy or alkylcarbonyl; R is alkyl, alkenyl or aryl; R′ isalkylene, alkenylene, arylene, arylenealkylene or alkylenearylene having2 to 5 carbon atoms, these radicals being able to be interrupted byoxygen and sulphur atoms or by amino groups; A is C(═O)O, OC(═O)O, C(O),O or OC(═O); U is an inorganically modified organic radical comprising asiloxane or carbosiloxane framework having at least two atoms that aresilicon or germanium or a carbosilane framework having at least one atomthat is silcon or germanium, said framework having 1 to 15 C atoms andup to additional heteroatoms that are O or N; a = 1, 2 or 3; b = 0, 1 or2; a + b = 3; c = 1, 2, 3 or 4; and d = 0 or
 1.


23. The method of claim 22, in which one or more silanes of the generalformula VIII are used as cationically polymerizable compounds:Y_(n)SiX_(m)R_(4-(n+m))  (VIII) in which X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″2; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R″ is hydrogen, alkyl oraryl; Y is a substituent that comprises a substituted or unsubstituted1,4,6-trioxaspiro-[4,4]-nonane radical; n = 1, 2 or 3; and m = 1, 2 or3, and n + m is less than or equal to
 4.


24. The method according to claim 21, wherein the reaction mixturecomprises at least one hydrolytically condensable compound of siliconand optionally other elements from the group consisting of B, Al, Sn,Pb, the transition metals, the lanthanides and the actinides, and/orprecondensates derived from said hydrolytically condensable compound,and the process further comprises a step of hydrolytically condensingsaid at least one hydrolytically condensable compound.
 25. The methodaccording to claim 22, wherein the reaction mixture comprises at leastone hydrolytically condensable compound of silicon and optionally otherelements from the group consisting of B, Al, Sn, Pb, the transitionmetals, the lanthanides and the actinides, and/or precondensates derivedfrom said hydrolytically condensable compound, and the process furthercomprises a step of hydrolytically condensing said at least onehydrolytically condensable compound.
 26. according to claim 23, whereinthe reaction mixture comprises at least one hydrolytically condensablecompound of silicon and optionally other elements from the groupconsisting of B, Al, Sn, Pb, the transition metals, the lanthanides andthe actinides, and/or precondensates derived from said hydrolyticallycondensable compound, and the process further comprises a step ofhydrolytically condensing said at least one hydrolytically condensiblecompound.
 27. The method according to claim 21, in which the reactionmixture comprises one or more compounds of the general formula VI,optionally in precondensed form, as at least one hydrolyticallycondensable compound of silicon:R_(e)(R¹⁰Z′)_(f)SiX_(4-(e+f))  (VI) in which X is hydrogen, halogen,hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR″₂; R isalkyl, alkenyl, aryl, alkylaryl or arylalkyl; R″ is hydrogen, alkyl oraryl; R¹⁰ is alkylene or alkenylene, these radicals being able to beinterrupted by oxygen or sulphur atoms or —NH groups; Z′ is halogen oran optionally substituted amino, amide, aldehyde, alkylcarbonyl,carboxy, mercapto, cyano, alkoxy, alkoxycarbonyl, sulfonic acid,phosphoric acid, acryloxy, methacryloxy, epoxy or vinyl group; e = 0, 1,2 or 3; and f = 0, 1, 2 or 3; with e + f = 1, 2 or 3.